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                                <span class="subtitle">Methods</span>
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                                    <li data-name="writefeatures"><a
                                            href="module-ol_format_GML-GML.html#writeFeatures">writeFeatures</a>
                                    <li data-name="writefeaturesnode"><a
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                <h1 class="page-title" data-filename="module-ol_format_GML-GML.html">Class: GML</h1>
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                <section class="content">

                    <header>
                        <h2 class="my-3">
                            <span class="ancestors"><a href="module-ol_format_GML.html">ol/format/GML</a>~</span>GML
                        </h2>
                        <br>



                        <pre
                            class="prettyprint source"><code>import GML from '<a href="module-ol_format_GML.html">ol/format/GML</a>.js';</code></pre>


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                    <article>
                        <div class="container-overview">



                            <dl>

                                <dt class="">

                                    <div class="nameContainer">
                                        <div class="anchor" id="GML">
                                        </div>
                                        <h4 class="name">
                                            new GML<span class="signature">(<span
                                                    class="optional">options</span>)</span>



                                        </h4>

                                        <div class="tag-source">
                                            <a
                                                href="https://github.com/openlayers/openlayers/blob/v8.2.0/src/ol/format/GML.js">format/GML.js</a>,
                                            <a
                                                href="https://github.com/openlayers/openlayers/blob/v8.2.0/src/ol/format/GML.js#L16">line
                                                16</a>
                                        </div>

                                    </div>


                                </dt>
                                <dd class="">




                                    <div class="description">
                                        <p>Feature format for reading and writing data in the GML format
                                            version 3.1.1.
                                            Currently only supports GML 3.1.1 Simple Features profile.</p>
                                    </div>










                                    <table class="params">
                                        <thead>
                                            <tr>

                                                <th>Name</th>


                                                <th>Type</th>

                                                <th class="last">Description</th>
                                            </tr>
                                        </thead>

                                        <tbody>


                                            <tr class="">

                                                <td class="name"><code>featureNS</code></td>



                                                <td class="type">


                                                    <span class="param-type">Object.&lt;string, string></span>
                                                    |

                                                    <span class="param-type">string</span>

                                                    | undefined


                                                </td>



                                                <td class="description last">

                                                    <p>Feature
                                                        namespace. If not defined will be derived from GML. If multiple
                                                        feature types have been configured which come from different
                                                        feature
                                                        namespaces, this will be an object with the keys being the
                                                        prefixes used
                                                        in the entries of featureType array. The values of the object
                                                        will be the
                                                        feature namespaces themselves. So for instance there might be a
                                                        featureType
                                                        item <code>topp:states</code> in the <code>featureType</code>
                                                        array and then there will be a key
                                                        <code>topp</code> in the featureNS object with value
                                                        <code>http://www.openplans.org/topp</code>.
                                                    </p>
                                                </td>
                                            </tr>



                                            <tr class="">

                                                <td class="name"><code>featureType</code></td>



                                                <td class="type">


                                                    <span class="param-type">Array.&lt;string></span>
                                                    |

                                                    <span class="param-type">string</span>

                                                    | undefined


                                                </td>



                                                <td class="description last">

                                                    <p>Feature type(s) to parse.
                                                        If multiple feature types need to be configured
                                                        which come from different feature namespaces,
                                                        <code>featureNS</code> will be an object
                                                        with the keys being the prefixes used in the entries of
                                                        featureType array.
                                                        The values of the object will be the feature namespaces
                                                        themselves.
                                                        So for instance there might be a featureType item
                                                        <code>topp:states</code> and then
                                                        there will be a key named <code>topp</code> in the featureNS
                                                        object with value
                                                        <code>http://www.openplans.org/topp</code>.
                                                    </p>
                                                </td>
                                            </tr>



                                            <tr class="">

                                                <td class="name"><code>srsName</code></td>



                                                <td class="type">


                                                    <span class="param-type">string</span>

                                                    | undefined


                                                </td>



                                                <td class="description last">

                                                    <p>srsName to use when writing geometries.</p>
                                                </td>
                                            </tr>



                                            <tr class="">

                                                <td class="name"><code>surface</code></td>



                                                <td class="type">


                                                    <span class="param-type">boolean</span>



                                                    (defaults to false)


                                                </td>



                                                <td class="description last">

                                                    <p>Write gml:Surface instead of gml:Polygon
                                                        elements. This also affects the elements in multi-part
                                                        geometries.</p>
                                                </td>
                                            </tr>



                                            <tr class="">

                                                <td class="name"><code>curve</code></td>



                                                <td class="type">


                                                    <span class="param-type">boolean</span>



                                                    (defaults to false)


                                                </td>



                                                <td class="description last">

                                                    <p>Write gml:Curve instead of gml:LineString
                                                        elements. This also affects the elements in multi-part
                                                        geometries.</p>
                                                </td>
                                            </tr>



                                            <tr class="">

                                                <td class="name"><code>multiCurve</code></td>



                                                <td class="type">


                                                    <span class="param-type">boolean</span>



                                                    (defaults to true)


                                                </td>



                                                <td class="description last">

                                                    <p>Write gml:MultiCurve instead of gml:MultiLineString.
                                                        Since the latter is deprecated in GML 3.</p>
                                                </td>
                                            </tr>



                                            <tr class="">

                                                <td class="name"><code>multiSurface</code></td>



                                                <td class="type">


                                                    <span class="param-type">boolean</span>



                                                    (defaults to true)


                                                </td>



                                                <td class="description last">

                                                    <p>Write gml:multiSurface instead of
                                                        gml:MultiPolygon. Since the latter is deprecated in GML 3.</p>
                                                </td>
                                            </tr>



                                            <tr class="">

                                                <td class="name"><code>schemaLocation</code></td>



                                                <td class="type">


                                                    <span class="param-type">string</span>

                                                    | undefined


                                                </td>



                                                <td class="description last">

                                                    <p>Optional schemaLocation to use when
                                                        writing out the GML, this will override the default provided.
                                                    </p>
                                                </td>
                                            </tr>



                                            <tr class="">

                                                <td class="name"><code>hasZ</code></td>



                                                <td class="type">


                                                    <span class="param-type">boolean</span>



                                                    (defaults to false)


                                                </td>



                                                <td class="description last">

                                                    <p>If coordinates have a Z value.</p>
                                                </td>
                                            </tr>


                                        </tbody>
                                    </table>




                                    <dl class="details">





















                                    </dl>













                                </dd>

                            </dl>

                        </div>


















                        <h3 class="subsection-title">Methods</h3>

                        <dl>


                            <dt class="">

                                <div class="nameContainer">
                                    <div class="anchor" id="writeFeatures">
                                    </div>
                                    <h4 class="name">
                                        writeFeatures<span class="signature">(features, <span
                                                class="optional">options</span>)</span><span
                                            class="fa fa-arrow-circle-right"></span><span
                                            class="type-signature returnType">{string}</span>



                                    </h4>

                                    <div class="tag-source">
                                        <a
                                            href="https://github.com/openlayers/openlayers/blob/v8.2.0/src/ol/format/GML.js">format/GML.js</a>,
                                        <a
                                            href="https://github.com/openlayers/openlayers/blob/v8.2.0/src/ol/format/GML.js#L27">line
                                            27</a>
                                    </div>

                                </div>


                            </dt>
                            <dd class="">




                                <div class="description">
                                    <p>Encode an array of features in GML 3.1.1 Simple Features.</p>
                                </div>










                                <table class="params">
                                    <thead>
                                        <tr>

                                            <th>Name</th>


                                            <th>Type</th>

                                            <th class="last">Description</th>
                                        </tr>
                                    </thead>

                                    <tbody>


                                        <tr class="">

                                            <td class="name"><code>features</code></td>



                                            <td class="type">


                                                <span class="param-type">Array&lt;<a
                                                        href="module-ol_Feature-Feature.html">Feature</a>></span>




                                            </td>



                                            <td class="description last">

                                                <p>Features.</p>
                                            </td>
                                        </tr>



                                        <tr class="">

                                            <td class="name"><code>options</code></td>




                                            <td colspan=2 class="description last">

                                                <p>Options.</p>


                                                <table class="params">
                                                    <thead>
                                                        <tr>

                                                            <th>Name</th>


                                                            <th>Type</th>

                                                            <th class="last">Description</th>
                                                        </tr>
                                                    </thead>

                                                    <tbody>


                                                        <tr class="">

                                                            <td class="name"><code>dataProjection</code></td>



                                                            <td class="type">


                                                                <span class="param-type"><a
                                                                        href="module-ol_proj.html#~ProjectionLike">ProjectionLike</a></span>

                                                                | undefined


                                                            </td>



                                                            <td class="description last">

                                                                <p>我们正在写入的数据的投影。如果未提供，则将分配格式的<code>dataProjection</code>（在已设置的情况下）。如果未为格式设置<code>dataProjection</code>，则将特征返回至<code>featureProjection</code>.
                                                                </p>
                                                            </td>
                                                        </tr>



                                                        <tr class="">

                                                            <td class="name"><code>featureProjection</code></td>



                                                            <td class="type">


                                                                <span class="param-type"><a
                                                                        href="module-ol_proj.html#~ProjectionLike">ProjectionLike</a></span>

                                                                | undefined


                                                            </td>



                                                            <td class="description last">

                                                                <p>将由格式写入器序列化的特征几何图形的投影。如果未提供，则假定几何图形位于<code>dataProjection</code>中（如果已设置）；换句话说，它们不会被转换。
                                                                </p>
                                                            </td>
                                                        </tr>



                                                        <tr class="">

                                                            <td class="name"><code>rightHanded</code></td>



                                                            <td class="type">


                                                                <span class="param-type">boolean</span>

                                                                | undefined


                                                            </td>



                                                            <td class="description last">

                                                                <p>在写入几何图形时，遵循线性环方向的右手定则。这意味着多边形将具有逆时针的外环和顺时针的内环。默认情况下，坐标将按照构建时提供的方式进行序列化。如果<code>true</code>，则应用右手定则。如果为<code>false</code>，则应用左手定则（外环为顺时针，内环为逆时针）。请注意，并非所有格式都支持此功能。在写入几何图形时，GeoJSON格式会使用此属性。
                                                                </p>
                                                            </td>
                                                        </tr>



                                                        <tr class="">

                                                            <td class="name"><code>decimals</code></td>



                                                            <td class="type">


                                                                <span class="param-type">number</span>

                                                                | undefined


                                                            </td>



                                                            <td class="description last">

                                                                <p>坐标的最大小数位数。坐标在内部以浮点数形式存储，但浮点算术可以创建具有大量小数位的坐标，这在输出时通常是不需要的。在此处设置一个数字以对坐标进行四舍五入。也可以用于确保可以使用相同数量的小数位将读取的坐标写回。默认情况下不进行四舍五入。
                                                                </p>
                                                            </td>
                                                        </tr>


                                                    </tbody>
                                                </table>
                                            </td>
                                        </tr>


                                    </tbody>
                                </table>




                                <dl class="details">





















                                </dl>















                                <h5>Returns:</h5>
                                Result.
                                <br />




                            </dd>




                            <dt class="">

                                <div class="nameContainer">
                                    <div class="anchor" id="writeFeaturesNode">
                                    </div>
                                    <h4 class="name">
                                        writeFeaturesNode<span class="signature">(features, <span
                                                class="optional">options</span>)</span><span
                                            class="fa fa-arrow-circle-right"></span><span
                                            class="type-signature returnType">{Node}</span>



                                    </h4>

                                    <div class="tag-source">
                                        <a
                                            href="https://github.com/openlayers/openlayers/blob/v8.2.0/src/ol/format/GML.js">format/GML.js</a>,
                                        <a
                                            href="https://github.com/openlayers/openlayers/blob/v8.2.0/src/ol/format/GML.js#L38">line
                                            38</a>
                                    </div>

                                </div>


                            </dt>
                            <dd class="">




                                <div class="description">
                                    <p>Encode an array of features in the GML 3.1.1 format as an XML node.</p>
                                </div>










                                <table class="params">
                                    <thead>
                                        <tr>

                                            <th>Name</th>


                                            <th>Type</th>

                                            <th class="last">Description</th>
                                        </tr>
                                    </thead>

                                    <tbody>


                                        <tr class="">

                                            <td class="name"><code>features</code></td>



                                            <td class="type">


                                                <span class="param-type">Array&lt;<a
                                                        href="module-ol_Feature-Feature.html">Feature</a>></span>




                                            </td>



                                            <td class="description last">

                                                <p>Features.</p>
                                            </td>
                                        </tr>



                                        <tr class="">

                                            <td class="name"><code>options</code></td>




                                            <td colspan=2 class="description last">

                                                <p>Options.</p>


                                                <table class="params">
                                                    <thead>
                                                        <tr>

                                                            <th>Name</th>


                                                            <th>Type</th>

                                                            <th class="last">Description</th>
                                                        </tr>
                                                    </thead>

                                                    <tbody>


                                                        <tr class="">

                                                            <td class="name"><code>dataProjection</code></td>



                                                            <td class="type">


                                                                <span class="param-type"><a
                                                                        href="module-ol_proj.html#~ProjectionLike">ProjectionLike</a></span>

                                                                | undefined


                                                            </td>



                                                            <td class="description last">

                                                                <p>我们正在写入的数据的投影。如果未提供，则将分配格式的<code>dataProjection</code>（在已设置的情况下）。如果未为格式设置<code>dataProjection</code>，则将特征返回至<code>featureProjection</code>.
                                                                </p>
                                                            </td>
                                                        </tr>



                                                        <tr class="">

                                                            <td class="name"><code>featureProjection</code></td>



                                                            <td class="type">


                                                                <span class="param-type"><a
                                                                        href="module-ol_proj.html#~ProjectionLike">ProjectionLike</a></span>

                                                                | undefined


                                                            </td>



                                                            <td class="description last">

                                                                <p>将由格式写入器序列化的特征几何图形的投影。如果未提供，则假定几何图形位于<code>dataProjection</code>中（如果已设置）；换句话说，它们不会被转换。
                                                                </p>
                                                            </td>
                                                        </tr>



                                                        <tr class="">

                                                            <td class="name"><code>rightHanded</code></td>



                                                            <td class="type">


                                                                <span class="param-type">boolean</span>

                                                                | undefined


                                                            </td>



                                                            <td class="description last">

                                                                <p>在写入几何图形时，遵循线性环方向的右手定则。这意味着多边形将具有逆时针的外环和顺时针的内环。默认情况下，坐标将按照构建时提供的方式进行序列化。如果<code>true</code>，则应用右手定则。如果为<code>false</code>，则应用左手定则（外环为顺时针，内环为逆时针）。请注意，并非所有格式都支持此功能。在写入几何图形时，GeoJSON格式会使用此属性。
                                                                </p>
                                                            </td>
                                                        </tr>



                                                        <tr class="">

                                                            <td class="name"><code>decimals</code></td>



                                                            <td class="type">


                                                                <span class="param-type">number</span>

                                                                | undefined


                                                            </td>



                                                            <td class="description last">

                                                                <p>坐标的最大小数位数。坐标在内部以浮点数形式存储，但浮点算术可以创建具有大量小数位的坐标，这在输出时通常是不需要的。在此处设置一个数字以对坐标进行四舍五入。也可以用于确保可以使用相同数量的小数位将读取的坐标写回。默认情况下不进行四舍五入。
                                                                </p>
                                                            </td>
                                                        </tr>


                                                    </tbody>
                                                </table>
                                            </td>
                                        </tr>


                                    </tbody>
                                </table>




                                <dl class="details">





















                                </dl>















                                <h5>Returns:</h5>
                                Node.
                                <br />




                            </dd>

                        </dl>





                    </article>

                </section>




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